GENESIS (GENEralized Model for SImulating Shoreline Change) enables to simulate the long-term shoreline evolution caused by combined wave and currents actions. It is a one dimension model in which beach change is described in terms of the shoreline position. It is possible to take into acount diverse variety of structure: groins, jetties, breakwaters, seawalls and other engineering activity such as beach fills. The model then estimates the changes in longshore sand transport due to coastal structure effects.